1. Presuppositional – God doesn’t need to be defended, thus we begin with the “presupposition” that the Bible is God’s Word, His divine and perfect revelation of Himself and His will for mankind. All arguments are based strictly on this foundation (and any other presuppositions one can find).
2. Evidential  – Like a professional investigator, you piece together the evidence, from not only Scripture itself, but you are able to, by the predominance of evidence prove the Bible is what is claimed, that the claims within its pages are true, and that therefore faith is a reasonable response to the evidence.

In fact, there is a pretty serious theological battle that has been raging for pretty much the entire history of Christianity over which method is the correct method. But when one follows the narrative of Scripture, we actually see both used. For the witness to the Hebrew people, a great deal of presuppositional work is done, beginning with the common ground of God’s law and overall revelation in the Old Testament. But we also see evidential defense made by Paul in many scenarios, beginning not with statement as fact, but building a “logical” case for Christianity based on his own life, the miracles witnessed, the eye witness accounts of Jesus and the other first-hand “primary” evidence, coupled with existing Scripture to “prove” the Christian gospel as correct and true.

But the bigger purpose of apologetics is not to build biblical academics or to give bragging rights to the prideful.  Apologetics serve two purposes that both build up that foundation of 2 Timothy 4:2 – First in that it is to give confidence to the believer. When we not only know WHAT we believe, but WHY we believe it – when we know how to defend our faith, we strengthen that faith and the hope that is in us glows brighter. But the second aspect of apologetics is the outward witness – we can make the case for Christ in a world that is by default against the gospel.

But regardless of the apologetic form you prefer to focus on, they both must begin with understanding WHAT we believe.  For those of us who cling to the biblical platform of “Sola Scriptura” (Scripture alone), we believe that the Bible is sufficient and complete for all instruction and defense – “All Scripture is inspired (literally breathed out by God!) by God and profitable for teaching, for reproof, for correction, for training in righteousness…” (2 Timothy 3:16). Read the Bible. Study it. Find new ways to engage with the Word through not only personal reading, but group study. Challenge yourself, be willing to spend time and effort really learning what God has recorded for our benefit.

Plug in to resources by people who have dedicated their lives and often ministries to defending the Bible and the Christian faith. People like J. Warner Wallace are contemporary apologetics, but there are literally hundreds who have, though history, worked extensively to build an incredible defense, both from a Presuppositional and an Evidential basis.

But the very best source of learning to be able to give a defense of your faith, the the Bible itself, for it is truly sufficient!